o) b-2/2 +b-3/3 - b-4/4 = b+4/6 | * 12
6(b-2) + 4(b-3) - 3(b-4) = 2(b+4)
6b-12 + 4b -12 - 3b +12 = 2b +8
6b + 4b - 3b -2b = 12 +12 -12 +8
5b = 20 | :5
b = 4
п) 7d - 2/3 - 4(d+3)/5 +6 = 3(d+2)/2 | *30
10(7d - 2) - 24(d+30) + 180 = 45(d +2)
70d - 20 -24d -720 +180 = 45d +90
70d - 24d -45d= 90 +20 +720-180
d = 650